


The Little Merman

by ZWorld



Category: Shingeki no Kyojin | Attack on Titan
Genre: Crossover, M/M, Prince Eren, Prince Levi - Freeform, The little mermaid - Freeform, merman eren
Language: English
Status: Completed
Published: 2018-10-13
Updated: 2018-10-13
Packaged: 2019-08-01 10:30:58
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 4,991
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16282940
Author URL: https://archiveofourown.org/users/ZWorld/pseuds/ZWorld
Summary: Eren Yeager, a merman, has always been curious about humans and life beyond the shore. One night, as a ship passes over the water above his hideout, he makes a trip up to investigate - Only to find himself fall in love with a human prince.





	The Little Merman

**Author's Note:**

  * For [ReluctantHero](https://archiveofourown.org/users/ReluctantHero/gifts).



> This is a gift for the beautiful [Soapy!!!](http://soapy0-0.tumblr.com/)  
> Thank you for being such an amazing friend!  
> You can find her here as well! [ReluctantHero](https://archiveofourown.org/users/ReluctantHero/works)  
> Based on The Little Mermaid and this [beautiful fanart,](http://roxi4.tumblr.com/post/179008356004/what-would-i-give-to-live-where-you-are-what#notes) drawn just for her!

It started with simple curiosity.

 

Eren had always been curious; right from when he was young.

 

It all began with a small mysterious object he found one day with his childhood friend, Armin. Armin was a small, but very pretty, tropical fish. Usually his kind only came in blue and yellows; but Armin was special in having the ever so lightest blue strips along his lateral line. This alone caused him to be a bit of an outcast, to which allowed Eren to become friends with him. They both were unusual in their looks and rather sought after. Perhaps this is what caused them to be so intrigued of the world above - it was different and beautiful.

He must have been only a young merboy back then. Young, brave and ready to seek adventures with his fish friend. That day, they had lurked further out of his father’s palace than they ever had before. The water was warm, clear, and not a single current could be found. It were these conditions that aided him in spotting something sparkling from the sand they swam over.

The tiny speckle shined from the light streaming from above. It had caught his eye quite quickly from its blinding qualities. When he had swam down to pick it up; it was very small and something he'd never seen before. It was circular in shape with a hole in the centre, and a colour that he could not describe. On one end was an attached pearl, glistening its beauty at him. Both boys were excited to find the strange object and immediately knew where to take it to.

They had gone to Eren’s father, King Yeager, with many questions. Only to be scolded for having found such an object. It had apparently belonged to creatures called _humans_. An item that was forbidden to have and an interest that he must not ever delve into.

“ _They are dangerous_ ,” his father had warned him. Droned on for the rest of the daylight about how they would kill him should he ever show his face near one. Eren was near the brink of tears by the end of it, clutching the small treasure like his life depended on it. Poor Armin had taken the verbal beating too.

That never stopped his curiosity though. His father’s opinions of humans did not matter! He’d still keep searching for treasures, no matter how dangerous. As he grew older, Eren and Armin went on many adventures together. They’d find old shipwrecks and sunken dinghies that humans left behind. Somewhere along the line, his brightly yellow coloured friend had found them a hideout to stash all their findings. Although he had no idea what any of them were, he still held them dearly. He had hoped that someday many of them would make sense. Armin’s positive nature and wanderlust eyes of seeking the human world always urged him on for more exploring, no matter the cost.

The world of humans was so different than his - much more fascinating than the boring life he lead under the sea. He was the king’s youngest son. Pampered and always needing to act like a good boy. He had a reputation to uphold down in his father’s kingdom; and it only helped feed his interest in humans. It took his mind off the whispers, stares and words of pity that he’d always be second in line to his older brother, Zeke.

It wasn’t until he was twelve when he grew brave enough to swim to the surface. All the other merpeople always spoke deviously of humans. They were _barbarians_ and should you ever run across one, you’d have less than a second to live unless you can swim the other way quick enough. The high chance of finding one above the sea line was too high. No one ever went up there unless they had a death wish.

But Eren just had to know. He wanted to see one. He wanted to make sense of all the objects he had found over the years. He wanted to see what made them dangerous and hated by so many.

He swam through the strong currents of the warmer water. Fought through waves of white foam until he broke through the water. A part of him was disappointed to had reached the surface only to find vast amounts of blue water surrounding him. The air felt chilly - It made it feel colder than it had been down bellow. There was something that blew at his hair, forcing it to swift to the right and stick to his damp face. It was bitingly cold and his skin was starting to form little bumps - a sensation he had never felt under the sea.  

He continued to swim onward in hopes of finding something. Using his turquoise fin to push himself through the currents and with aid of his arms breaking any lapping waves, he covered quite the distance. Without Armin by his side at that moment, he could travel faster than he normally would have.

It was that day when he met Hanji. On a small rock in the middle of nowhere had sat a strange looking creature. It was hairy and loud. Brown and small. And making a racket as it jumped around, pecking at what looked like a dead fish.

She had introduced herself as a brown noddy bird and was delighted in seeing a merman again. She had told him she rarely saw his kind, but had heard many of her flock speak hush tones of them. She explained to him what she was; how she could fly. She was eccentric and quite often clumsy. She often slipped from the perch of her rock. It took Eren a long time before he stopped laughing at her antics. But most of all, she loved to talk for many daylight hours about all the things Eren wanted to know since the very first treasure he’d found.

If anything, Eren’s curiosity got the better of him by then. Hanji introduced an entirely new world to him. Lead him to what was called a beach and land. Showed him how nice it was to bake under the hot sunlight, causing his skin to glow almost like caramel. Explained and named every object he and Armin had brought to her. She taught him how to use each one - even the pieces of soft fabric.

She explained how humans interacted with each other and what they looked like. Had said that his upper body looked so similar to those who were called “boys” and yet, how is lower looked that of a beautiful fish. However, gravely told him that they didn’t have ears like his nor long fingernails that were sharp and claw-like. Rather, theirs was stubbly to not get in the way of them gripping to things.. Often times with the females, they’d be colourful; like the coral you could find not too far from them.

The merboy couldn’t quite comprehend how legs, feet, or the clothing really worked for the lower half. Not until his friend found a particular shipwreck many miles off from Eren’s hideout. There he found many wonders, including folded pieces of something hard, containing thin sheets of something smudged. It was a big, heavy rectangular object. It had a peculiar thing attached - it looked like mermaids, but fully dressed in what humans wore, and of course had no fins.

It was as if his love and fascination for humans had grown vastly once he knew what they truly looked like.

 

It wasn’t until many years later that he saw humans up close for the first time.

Particularly, an extremely handsome _man_.

A _human_ man who he fell in love with.

It was meant to be his big debut as prince on that particular day. He was old enough to start doing some honourable roles around the kingdom his father had ruled. Instead of being a responsible merman, Eren and his little friend had gone exploring one final time at their favourite shipwreck.

Only - it caused him more strife than he first planned. It ended with a couple of punches and scraps of sharp, clawed-nails against a great white shark. He won. He was strong enough. He was older now and he knew how to fight. He’d grown longer and stronger. His torso filled out with muscle and his biceps hard with years of exploring. His hair longer than he had as a merboy; long brown strands floated behind him wherever he went. And his tail had began to glow the most beautiful shade of turquoise, matching his wondrous eyes. He was often the highest spoken about merman in the kingdom. Many had their eyes set on him - but his mind was filled with many other wonders.

With physical growth also came mental growth. He knew now to keep his mouth shut. He’d learnt to take his father’s reprimanding of him seeking humans. Of his keen interest. Since he was a boy he was constantly being told off over his curisority. He had responsibilities down under in the sea to worry about.  What was the point in being a crown prince when you were wanting to naively explore and get yourself killed by _barbarians_ , his father often shouted.

It ended with his father banishing him from seeking more objects. Of even going up to the surface. Apparently, word had gotten round that a few merpeople had seen him swim up there earlier on the day, rather than being at the ball that had been held. The king had order for Mikasa, a small black crab that had a long lineage with his family, to follow him and keep a close eye on the merman. She was a new recruit who along with her family always kept close to the royalty. Her father was the King’s right hand man. They always took care of each other throughout the years.

Despite being fond of his newly appointed caretaker, Eren was angry. His father could not understand! These humans were beautiful. Their world so much more fascinating and exciting than it was down bellow! He didn’t want to be stuck under the sea anymore! It was too boring!

Armin had tried to calm Eren down as they swam away. Allowed the merman to sulk in his hideout for a minute before swimming through Eren’s long brown locks of hair; trying to cheer him up in any way. Even helped put away the only two last items they had found before the fight with the shark.

The hideout was a cylinder shaped cave. Grooves lined the walls, allowing almost makeshift bookshelves for Eren to place his findings. It had become quite wondrous and tightly packed over the years. It was perfectly lit by a small opening at the top of the cave. Daylight would shine in, making all their treasures sparkle.

“Eren, are you going to be okay?” Armin asked in a small voice, nudging his small body against the merman’s cheek.

“If only I could make him understand, Arm. I just don't see things the way he does. I don't see how a world that makes such wonderful things... could be bad,” Eren sighed, allowing himself to lay back onto the sea floor.

Defeated and tired, he gazed up to the small opening at the top of the cave. Oh how he wished that he could go up there someday. To magically transform legs and to explore all the uncharted lands he’d heard Hanji speak of. He wanted to talk to humans and see how they were with his very own eyes.

He tried to ignore Mikasa as she scribbled about, groaning and muttering to herself about all the pieces of junk in the cave. Armin had taken onto watching Mikasa sift through some objects with her sharp claws. He giggled when he saw a particular red cloth take her interest. Perhaps they could talk her into having similar opinions on humans. She was still a new recruit and practically their age. She had yet to be brainwashed by the King and the soldiers.

Eren began to hum quietly; a tune he had dreamt up one day. Lyrics he had over time formed with Armin on their quiet days; when the sea was especially clear and blue. When the light from above shone brightly through and warmed even the deepest of waters.

Stretching his arms widely above him, feeling the sand scraping against the few speckled scales on his forearms. He allowed his hair to be covered with the fine dust, his eyes slowly became low lidded as he whispered, “Out of the sea, wish I could be…”

Before he continued, the cave suddenly grew dark as something floated over the only opening for light to seep through overhead. His eyes flashed open as he heard distant noises with his sensitive ears.

Curious; he immediately swam out of the cave, Armin and a scuttling Mikasa chased after him, calling his name.

“Eren!”

“Eren, where are you going!? Slow down!”

But Eren did not stop. In the distance he could see an oval shaped object floating by the sea line. It was dark brown and reminded him of a less broken version of the shipwrecks he’s explored with Armin.

 

 _A ship_. A moving ship!

 

Joy filled his heart at the thought of humans being just above the water surface! Flashes of colours danced against the darkening water; growing more and more vibrant the closer he got. His heart was pumping wildly as he drew near. He broke through the waves, only a few metres away from the moving ship.

A strange sound filled his ears. It was loud alongside the bangs that shot overhead of the boat. The explosions released mesmerising colours, looking similar to small corals. His ears twitched to listen closely - he could hear laughter in the distance with that strange beat again. It almost sounded like when the mer-musicians played the drums. His eyes filled with wonder as he watched in a trance. He didn’t even notice Mikasa and Armin joining next to him.

“Eren, what - what are you- jumpin' jellyfish! Eren! Eren, we need to go back!” Armin screamed over the screeching noise and blast of greens.

“It’s dangerous! If your dad hears about this, we’re going to be deadfish!” Armin tried again, bumping himself against the merman’s arm.

Without taking much of a glimpse or care to his small friend, Eren began swimming after the ship. He flew into the air with his powerful tail, diving back down with his extended arms. It was the quickest way to get to the ship with the rough water. He didn’t care if it was dangerous! He just wanted to see humans! Just a small peek! It wouldn't hurt!

And what a sight it was. Using a big passing wave, he was above to leverage himself high enough onto the boat to grip at the decking. His biceps strong enough to hold him up as he peeked at what was on the deck.

 

_Humans._

 

Humans were cheering and laughing. _Dancing._ That’s the word that Hanji had mentioned. Jumping from one leg to another. There were so many of them. All dressed in shimmery clothes and black… suits? Was that the word Hanji had taught him? They all looked stunning with the glow of light around them.

But what caught his eye the most was a _particular_ human. He was on the far side of the boat, leaning against the railing. He had his arms crossed and looked like a thousand beautiful pearls put together. Paler than any other person on the ship, but incredibly handsome. Eren had never, ever seen a merperson look as beautiful as that human. His breath caught in his throat when the man had looked at something in his direction. His heart began thudding erratically and his body shivered all at once.

Eren lifted himself up, crossing his arms on the wooden deck, staring dazedly at the man. His hair was incredibly dark and beautiful against pale skin. His stature on the smaller side, but looked beautifully built under all those fabrics. Mesmerised and stunned, Eren knew he’d never have eyes for another.

“Eren! Funny seeing you here!?” A familiar voice squawked. The young merman looked down to find Hanji standing next to his bent elbow, looking at him curiously.

“Quite the show, eh?” She cackled.

“Hanji, be quiet! They'll hear you!” Eren swished his hand about, getting worried about causing a distraction.

“Oooh, I gotcha, I gotcha, catching a sneaky look, are you?” She teased, settling down against his arm.

Still stunned and gazing ahead at the human man on the other side through the legs of others, he whispered dreamily, “I've never seen a human this close before. Oh - he's very handsome, isn't he?”

Before Hanji could retort, another human had shouted an order for everyone to quieten down. The pair watched as they all interacted. An older looking man with long black hair introduced the one who caught his eye.

Apparently his name was _Levi_ and it was his _birthday_.

 

_Levi._

 

Eren had tried to move his lips to that name. Testing out the movement with a tongue, but struggling to do the word justice. He wasn’t used to rolling it against his top teeth. It was beautiful though. A word they never used under the sea.

A tall, much lighter haired man had joked next to him. They looked to be good friends, Eren thought. He spoke of Levi needing to step up his game. He was becoming too old. The country was begging for their crown prince to find a partner. The merman couldn’t really understand what it all meant. The tall one removed himself from Levi with a laugh, walking towards a huge object with fabric hanging over it. With a peculiar look on his face, the lighter haired man pulled it off. It revealed a statue of Levi himself.

“Prince Ackerman,” Hanji whispered to Eren. He assumed that was what was written on the plaque underneath.  

“What the everloving fuck did you get me, Erwin?” The man spoke at last, seemingly unimpressed. Eren all but swooned. A voice so incredibly deep and powerful. He could happily listen to it for days on end.

A hoard of laughter filled the boat, the longer haired man who introduced Levi before slapped his shoulder. “We wer’ hopin’ it would be fer’ yer’ marriage someday. But you and yer’ sourpuss ass keep failing every bud we can get, ‘yer kno?”

Levi scoffed, shrugging the hand off himself. Crossing his arms, he began walking towards Eren and Hanji. With a small startled yelp, the merman pushed himself down, hanging onto the deck with just the tips of his fingers; strong claws dipping into the wood.

“Maybe you’ll be lucky and it’ll hit me someday in the face. You know, like light-”

A struck of something loud and rumbling echoed off in the distance. The noise ringed in Eren’s sensitive ears; he couldn’t help but let go and dive back down into the water. He rose to the surface quickly, watching the boat from the stormy water. The human had been so close. Levi was just mere inches away from him. It had been so exhilarating!

“Eren! A storm. It’s coming. We have to go!” Mikasa cried, reminding Eren that his friends had been waiting for him this entire time. It surprised him that he hadn’t realised the waves had picked up over the short while. He should have noted it when they had been large enough to help him grip onto the ship.

But it was as if his father’s banishment had sixth sense. It was like the storm had came out of nowhere - stopping Eren from ever truly seeing humans.

The waves picked up quickly. They became strong, tossing the boat up and down like it weighed nothing. Screams could be heard until an echoing clap of thunder filled the night sky. A massive gust of rain and wind lashed from above as a result. The droplets stung Eren’s skin, almost like the prickles of sea urchins he used to play with as a young boy.

As he watched the ship lose control through the haze of rain and deafening thunder - he couldn’t help to worry about the humans on the ship. They couldn’t swim here. They wouldn’t survive! Spur of the moment, he chased after the boat with all his might; grinding teeth as he fought the stormy rapids.

It was as if he had a premonition about these humans. A particular thunderstrike hit a shaft on the large ship; causing an explosion. He didn’t even have a name for the red monstrous heat coming from the ship after an instant.

He began to feel at ease as smaller boats dropped into the water; men and woman inside them. He tried to draw as close as he could to make sure the man who held his interests was safe too.

“Levi! Get off the ship, now!!” The lighter haired man called from one of the boats.

Eren gasped, coming to realise that Levi wasn’t safe just yet. He fought his way to the red ship, heat emitting from it. Even the water was starting to feel warm. Just before he could search what was left of the boat, another explosion erupted.

With half lidded eyes; Eren saw something heavier fly into the sky along with the debris. Immediately recognising the human man; he swam after it.

With a wildly beating heart, hair sticking to his face, and stinging of the rain, the merman tried to catch Levi as he landed into the stormy water. As quickly as he was under water from the impact, Eren swam up to the surface so the man wouldn’t drown. He grabbed him tightly under the arms from behind, revelling in the hard muscles he found. Levi was warm, sturdy, and nothing like any merperson ever felt like. Eren couldn’t help but hold the body against himself in a tight embrace for a short amount of time, just savour the moment.

Not long after, with all the energy he had left and with the guidance of Armin; he started pulling the darker haired man to safety.

By the time they finally saw dry land in the distance, the morning sun was already starting to peek through the clouds. Hanji had joined them once the storm settled and helped them towards a safe place. She had even guided Eren to a spot to lay Levi on the sand. Armin and Mikasa opted to stay in the ocean whilst Eren made sure the man was alright.

Safely placed by a spot protected by rocks on one side, Eren stayed with the human.

He couldn’t help his eyes wandering. The man’s beautiful clothes had been devastatingly ruined. He no longer had shoes. His pants ripped in a few places, revealing sections of pale skin. His shirt was no longer useful either. The jacket had been lost, and the shirt itself ripped to shreds, showing off the human’s torso to Eren’s curious eyes.

He could not stop his hands when they began to move. He ran fingertips lightly over the human’s forearm, feeling soft black hairs tickle his fingers. He made sure to be gentle to not scratch Levi with his clawed nails. It was rather odd that Levi had fine hairs compared to the few scatters of scales Eren had himself on his forearms. He smiled as he noticed how nicely built the torso was, so similar to his own and yet so different. Should this human have been a merman - he too would have been sought after by many. And then his eyes met the most beautiful face he’d ever seen up close.

Light pink lips, black hair that contrasted against pearl pale skin. Mesmerised, he allowed himself to touch the soft cheeks. They were cold to the touch, but he felt some warmth under there. He allowed his fingers to brush away the droplets of water. Could feel the small puffs of air coming out of the other’s nose. Eren’s cheeks became hot as he continued to gently stroke the unconscious man. His heart fluttering gently with every breath he drew, his stomach churning in the most exciting ways. It was a feeling he wished he could have for the rest of his long life.

Levi was the most handsome human he had ever seen. The only human he ever wanted to see again. He wanted to continue staring lovingly at the man, holding every memory he could.

Curiosity was never going to fulfill him. He wished he could stay here forever, with this human. He wished he could wake up and they could speak. That he would magically gain a pair of legs and never have to go back into the ocean. He could help Levi find his friends and home. He would do whatever in his power to have Levi fall in love with him whilst at it - to bond and to live happily together like all other merpeople did.

 _Oh how he ached_.

“So, do you think he’s alive?” Hanji asked, breaking Eren’s magical moment.

Realising that was probably the first thing he should have done, he began to panic.

“How- how do you tell!?”

“Hm… let’s see. I think they,” Hanji muttered, jumping her way towards Levi’s feet. She held her head against the wet foot and made a few sad chirps, replying with, “It's hard to say. Oh, I - I can't make out a heartbeat.”

Eren almost had tears welling up in his eyes and a sense of dread in his heart until he heard a groan. A low smatter of words and a couple of heavy puffs. Turning his head towards Levi again, his heart leapt when he saw the man waking up!

“No, look! He's breathing!” Eren rejoiced. “He's so beautiful,” he whispered, using a gentle finger to brush away soft black strands. Levi’s eyes fluttered as he searched for the noise.

The merman began humming the song from the day before. With half lidded eyes and wet lips, he smiled at Levi, running the back of his fingers softly against warming cheeks. His other hand rested against Levi’s torso, wanting to keep close as possible.

“ _What would I give to live where you are… What would I pay to stay here beside you… What would I do to see you smiling at me…_ ”

Levi’s pink lips twitched, a small corner lifting into a smile as a soothing tone filled the air. His head turned, seeking the voice.

“ _Where would we walk? Where would we run? If we could stay all day in the sun? Just you and me, and I could be, part of your world..._ ”

The young merman leant forward, watching small slits of stunning grey orbs meet his own. Felt a warm breath against his own face as he neared, breaking into a toothy smile the closer they came to meeting lips.

 

“Levi!!”

“Levi is that you!!?” Sudden calls came from the distance.

Eren immediately lifted himself up, realising he was only mere inches away from the human. The thought of being caught by anyone else suddenly scaring him. This was dangerous! He had to go! He truly didn't want to leave Levi behind - but he didn’t know how dangerous the other human could be!

Hanji tried to cause a distraction by flying towards the man searching for Levi. Eren used his strong arms to crawl towards the nearest body of water. Once he reached it, he swam quickly through an opening and into the main sea, finding Armin floating above the surface and Mikasa settled on a rock. From this view, a shudder came over him as he realised they saw everything that he had done.

“Thank god you’re alright! We were all so worried about you!”  Eren heard Erwin huff as he helped the shorter man up from the sand.

Levi looked out towards the sea all confused, unsure if his mind was playing tricks on him or not. His head was extremely heavy and his body swaying ever so slightly.

“Are you alright, Levi?” The blonde asked.

“A guy - rescued me... He was - singing... He had the most - _beautiful_ voice,” he muttered, suddenly losing his footing and falling back.

Erwin grabbed hold of his shoulders, chuckling. “Ah, Levi. I think you've swallowed a bit too much seawater. Let’s get you home, hm?”

Eren watched the exchange longingly. Wishing and hoping that things would turn out differently. What he would have given to have joined the two men on their walk back to their home - to never leave Levi’s side.

“We just gotta forget this whole thing ever happened,” Armin whispered from Eren’s left.

“King Yeager will never know. You won't tell him, I won't tell him. We will keep this a secret,” Mikasa agreed. “Let’s go, Eren. Before King Yeager starts looking for you.”

But it all fell on deaf ears. The merman had his eyes trained on the two distancing figures with a saddening heart. He bit his bottom lip, gripping the rock he was hiding behind to push himself up for one last look. The ache in his heart and belly growing stronger the smaller the two humans became. He almost wanted to weep as he saw the shorter of the two take a look back at the beach as he waddled. The pain was enough to tell Eren what he had to do. He’d have to find Levi again. Find a way to capture the man’s attention. He just hoped the man would return to this beach.

With a final deep breath, he sang out with finality, “ _I don't know when, I don't know how, but I know something's starting right now. Watch and you'll see, someday I'll be, part of your world….!_ ”

  
  
  
  
  


 

 

_To be continued~_

 


End file.
